Trevor Knight of the Oklahoma Sooners celebrates a touchdown against the Alabama Crimson Tide during the Allstate Sugar Bowl at the Mercedes-Benz Superdome. (Jan. 2, 2013) Photo Credit: Getty Images

NEW ORLEANS - Bob Stoops declined to announce a starting quarterback before the Sugar Bowl, and when freshman Trevor Knight took the field on the Sooners' first possession, Alabama's defenders couldn't have anticipated what was in store.

Knight completed a Sugar Bowl-record 32 passes for 348 yards and four touchdowns, and No. 11 Oklahoma took down third-ranked Alabama, 45-31 on Thursday night.

His Big 12 team vanquished an Alabama (11-2) squad that had been ranked No. 1 much of the past three seasons, winning the previous two national titles before its shot at a third straight was derailed by Auburn on the last play last month in the Iron Bowl.

AJ McCarron passed for 387 yards and two TDs, but his two interceptions set up Oklahoma TDs, and his fumble, returned for a score in the final minute, sealed 'Bama's first two-game skid since its Sugar Bowl loss to Utah in January 2009. McCarron, meanwhile, lost his last two starts after going 36-2 before those games.

Freshman Derrick Henry's 43-yard run in the third quarter pulled Alabama to 31-24, and the Crimson Tide defense forced four punts while giving up only one first down in the third quarter. But Alabama was unable to add another score before the Sooners starting moving the ball again early in the final quarter.

Knight lofted a perfect pass to Lacoltan Bester for a 34-yard gain to the Alabama 9. Shortly after, Knight rolled left all the way to the sideline before rifling a touchdown strike to Sterling Shepard, making it a two-touchdown game again with 10:44 left.

Henry, a 6-foot-3, 238-pound true freshman, pulled Alabama back with in a score once more when he turned his first career completion into a tackle-shedding 61-yard TD with 6:22 still to go.

But Oklahoma was able to burn several minutes off the clock, and then Oklahoma registered its seventh sack when Eric Striker stripped McCarron, and Geneo Grissom returned it 8 yards for a score.

Both teams entered the Sugar Bowl with defenses ranked in the top 15 nationally, but quarterback play dominated a first half highlighted by five passing plays of 43 yards or longer, three of which went for scores. But McCarron threw two interceptions twice, each time setting up Sooners TDs on the very next play.

Alabama took the opening kickoff and scored in four plays. McCarron hit Amari Cooper for 15 and 53 yards, and T.J. Yeldon ran it in from the 1 two plays later.

It appeared to be getting worse for the Sooners when Alabama's Landon Collins made a diving interception of Knight's tipped pass, but Oklahoma got it right back when Gabe Lynn picked off McCarron's pass on the next play. One play later, Knight found Bester down the right sideline for a 45-yard score to tie it at 7.

On Alabama's next drive, McCarron found DeAndrew White for a 63-yard gain to set up Cade Foster's field goal, but the Sooners took their first lead when Knight found Jalen Saunders, who reached the ball across the goal line as he was being brought down.

McCarron's pinpoint deep pass down the middle to White for a 67-yard TD strike gave the Tide the lead right back early in the second quarter before the Sooners tied it at 17 on Michael Hunnicutt's 47-yard field goal.

Alabama appeared on the verge of a go-ahead score when Yeldon fumbled on the Oklahoma 8. The Sooners then methodically reached mid-field, where they converted a fourth-and-1. On the next play, Knight hit Saunders in stride down the right sideline for a 43-yard score.

McCarron's second interception, snagged by Zack Sanchez and returned to the 13, set up Shepard's 13-yard score around the right end, giving the Sooners a stunning 31-17 lead. The Tide drove into field goal range in the final minute of the half, but Foster missed a 32-yarder, leaving Oklahoma with two-TD lead at halftime.

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